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Date: Sat, 9 Aug 2014 10:39:20 +1000
Subject: Re: Newbie needing some help
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:75919

On Sat, Aug 9, 2014 at 10:32 AM, Chris Kaynor <ckaynor@zindagigames.com> wrote:
> The main issue I can see with that idea is that the exception will keep a
> reference to the database connection (as with all locals), so unless you
> explicitly close it within a finally clause, the database connection could
> still be left hanging, and thus no rollback will occur.

To clarify: The simple example I used there was assumed to be the
entire program, meaning that the process will terminate on exception.
No worries about resource release then!

This kind of model works nicely for anything that reads from one
source and writes into the database, or processes data from the
database back into the database, or anything like that. The general
assumption is that an unexpected exception should be treated as fatal
- just write to the console and terminate. While this might seem like
the simplest 1% of cases, it's able to handle a lot of real-world
situations. And since it takes no extra code, it's the perfect way to
start :)

ChrisA